The present invention concerns a standard construction unit and building enclosures made therefrom. More particularly, the present invention concerns precast units which may be made in a standardized configuration and assembled at the construction site to form a wide variety of buildings such as single or multiple-story buildings.
Over the years, numerous schemes have been advanced for providing more or less standardized prefabricated units capable of being assembled into a building or other structure. For example, an early patent, U.S. Pat. No. 375,999, shows an arched stone or concrete pavement block utilizing metal tie rods and adapted to be received within a supporting foundation to support a pavement surface. U.S. Pat. No. 457,984 shows a ribbed wall plaster construction having a ribbed side and a flat side from which flat surfaced walls may be assembled. U.S. Pat. No. 1,477,665 shows a concrete building assembled from individual concrete slabs which are pinned together by reinforcing rods which extend through all the slab sections of a wall. U.S. Pat. No. 1,393,996 shows a concrete building structure in which walls, floor and ceiling may be assembled from precast concrete slabs which are tied together by tie rods and a groove construction.
U.S. Pat. No. 2,171,338 shows a building member comprising U-shaped cross-section channel members having slotted flanges and adapted to enclose structural steel members. U.S. Pat. No. 3,101,572 shows U-shaped structural members of glass to form walls, floors, etc. Other U.S. patents employing precast slab construction and typical of numerous other patents in the field are U.S. Pat. Nos. 1,421,007; 1,666,199; 2,160,773 (which shows building blocks flat on one side and concave on the other with connecting wire loops embedded in the blocks) and 2,116,946.
There are numerous problems associated with attempts to use precast building elements to fabricate structures and some of these are illustrated by some of the above-mentioned U.S. patents. One common problem is the requirement to provide a supporting steel structure for the precast elements. Another is the requirement to provide numerous different configurations and sizes of the precast panels or units for floors, walls and roofs in order to provide a complete structure made therefrom. This disadvantage often requires a precast panel to be custom designed for each job and loses much of the advantage otherwise to be gained from prefabrication of parts.
Another difficulty with many of the prior art attempts is that more or less complex panel designs must be provided, as well as numerous tie rods, connecting fixtures and the like, all of which increases the complexity and number of parts required and correspondingly complicate the construction and assembly techniques required. This requires skilled or highly experienced labor and supervision to erect the structure. The latter factor is particularly significant in areas where it is desired to provide employment for relatively unskilled workers or where sufficient numbers of skilled and experienced workers are unavailable or their labor costs exceedingly high.
Not the least of the problems associated with buildings assembled from precast modular units of the prior art is their lack of aesthetic appeal. Precast concrete buildings are generally afflicted by aesthetically unpleasing appearance with virtually no possibility of providing a varied or pleasing design from standardized precast parts.
Yet another difficulty with structures assembled from prior precast standardized units is a limited structural strength which normally requires the provision of an additional steel framework, particularly if a multiple stored building is to be provided.
The object of the present invention is to provide a novel modular construction element and structures made therefrom which overcomes problems such as the foregoing and which provides a standardized readily prefabricated modular unit which may be assembled to form a wide variety of aesthetically attractive structures by relatively unskilled labor and without the necessity of employing complicated fastening means, accessories or construction techniques.
It is another object of the present invention to provide a novel modular standard construction unit which is easily and relatively inexpensively fabricated, which is of standard configuration and which may be employed in modified forms to provide the walls, floors and ceilings of a building structure.
It is another object of the present invention to provide such a novel modular construction unit made of reinforced cast concrete.
It is another object of the present invention to provide a novel building structure made from modular standard construction units as above which structures may be varied in form, have a pleasing aesthetic appearance and which may be readily assembled by relatively unskilled labor. Other objects and advantages of the present invention will be apparent from the following description.